Sept. 23 (UPI) -- The Department of Homeland Security contacted election officials in every state to clarify whether or not they were target by Russian hackers during the 2016 presidential election.

Homeland Security had found evidence of Russian activity in 21 states earlier this year, but notified the individual states that were targeted for the first time on Friday after months of complaints from election officials due to the lack of information, NPR reported.

"We heard that feedback," Bob Kolasky, deputy undersecretary for DHS's National Protection and Programs Directorate, said. "We recognize that it is important for senior state election officials to know what happens on their state systems."

Election officials from 12 states publicly announced their systems had been targeted by Russian hackers during the election.

Illinois was one of the few states in which hackers successfully infiltrated computer systems, but officials said there was no evidence the hackers tampered with voting machine, the Washington Post reported.

Hackers in Arizona didn't compromise the state voter registration system or any county system, but did steal the username and password of a Gila County election official.

State offices in Washington and Connecticut announced that hackers tried to break into their state election systems, but were ultimately unsuccessful.

"What this boils down to is that someone tried the door knob and it was locked," Wisconsin Elections Commission spokesman Reid Magney said.

Homeland Security had previously only notified those with "ownership" over election systems, including many private companies.

Following Friday's phone calls the National Association of Secretaries of States, which represents state election officials, was pleased state officials were notified.

"Most importantly, DHS acknowledged that they had contacted the wrong people at the state level and will rectify that going forward by communicating with each state's chief election officials," spokesman Stephen Reed said. "Finally finding out this information from DHS allows the chief elections officials to move forward on this matter."

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